This invention relates to an improvement for a knob switch device in which an operating knob can be operatively rotated and depressed, and more particularly, to an improvement in a knob switch device in which rotation of the operating knob turns on one switch and in which axial depression of the operating knob turns on two switches in such a manner that the operating knob is automatically rotated during such axial depression.
In a conventional knob switch device for automotive wipers, for example, the device is provided at a distal end of a lever with an operating knob which is capable of rotating and axial movement. Rotation of the operating knob causes a wiper switch to be turned on to operate the wipers. The axial depressing of the operating knob causes a washer switch to be turned on to spray a washing liquid and, at the same time operate the wipers through a predetermined cycle.
The above-described device is arranged to operate only one switch by the depressing movement of the knob for energizing two motors i.e., a washer motor for spraying the washing liquid and a wiper motor. Therefore, when only the washer switch is turned on by depressing the knob, the wiper motor must be operated by using a special electrical circuit such that the wiper motor is operated for a predetermined period of time while the washer motor is operated. A problem with the conventional knob switch device arises out of the electrical circuit being complicated.